Receivables (Gross Write-offs For Accounts Receivable) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Gross write-offs for accounts receivable, originated in 2022	$ 3	$ 8
Gross write-offs for accounts receivable, originated in 2023	2	2
IPL [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Gross write-offs for accounts receivable, originated in 2022	2	5
Gross write-offs for accounts receivable, originated in 2023	1	1
WPL [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Gross write-offs for accounts receivable, originated in 2022	1	3
Gross write-offs for accounts receivable, originated in 2023	$ 1	$ 1